Add mod live reload ability

Allow mod to reload script files while Noita is running.

files/libraries/noita-api/compatibility.lua

@@ -5,8 +5,6 @@
 
 -- Some code to make Noita's lua conform more to standard lua.
 
--- TODO: Make Noita-API module to work with several mods using it
-
 -- Stupid way to prevent this code from being called more than once per sandbox.
 -- Calling this lua file with dofile_once would still cause the setup function to be called multiple times.
 if _NoitaAPICompatibilityWrapperGuard_ then return function(dummy) end end
@@ -123,7 +121,7 @@ local function setup(libPath)
 	package.path = package.path .. "./" .. libPath .. "?/init.lua;"
 
 	-- Add the library directory of Noita itself.
-	package.path = package.path .. "./data/scripts/lib/?.lua;"
+	package.path = package.path .. "./data/scripts/lib/?.lua;" -- TODO: Get rid of Noita's lib path, create replacement libs for stuff in there
 end
 
 return setup

files/libraries/noita-api/live-reload.lua

@@ -0,0 +1,50 @@
+-- Copyright (c) 2022 David Vogel
+-- 
+-- This software is released under the MIT License.
+-- https://opensource.org/licenses/MIT
+
+-- Allows Noita mods to reload themselves every now and then.
+-- This helps dramatically with development, as we don't have to restart Noita for every change.
+-- To accomplish this, we need to override the default behavior of dofile and some other things.
+
+local LiveReload = {}
+
+local oldDofile = dofile
+---Overwritten dofile to execute a lua script from disk and cirumvent any caching.
+---Noita for some reason caches script files (Or loads them into its virtual filesystem)(Or caches compiled bytecode), so reloading script files from disk does not work without this.
+---
+---This is not fully conform the the standard lua implementation, but so isn't Noita's implementation.
+---@param path string
+---@return any result
+---@return string|nil err
+function dofile(path) ---TODO: Consider moving dofile into compatibility.lua
+	local func, err = loadfile(path)
+	if not func then return nil, err end
+
+	local status, res = pcall(func)
+	if not status then return nil, res end
+
+	return res, nil
+end
+
+---Reloads the mod's init file in the given interval in frames.
+---For reloading to work correctly, the mod has to be structured in a special way.
+---Like the usage of require and namespaces.
+---
+---Just put this into your `OnWorldPreUpdate` or `OnWorldPostUpdate` callback:
+---
+---	LiveReload:Reload("mods/your-mod/") -- The trailing path separator is needed!
+---@param modPath string
+---@param interval integer
+function LiveReload:Reload(modPath, interval)
+	self.Counter = (self.Counter or 0) + 1
+	if self.Counter < interval then return end
+	self.Counter = nil
+
+	local res, err = dofile(modPath .. "init.lua")
+	if err then
+		print(string.format("Error reloading mod: %s", err))
+	end
+end
+
+return LiveReload

init.lua

@@ -20,9 +20,10 @@ end
 -- Load library modules --
 --------------------------
 
-local Coords = require("coordinates")
 local CameraAPI = require("noita-api.camera")
+local Coords = require("coordinates")
 local DebugAPI = require("noita-api.debug")
+local LiveReload = require("noita-api.live-reload")
 local Vec2 = require("noita-api.vec2")
 
 -----------------------
@@ -47,6 +48,14 @@ dofile("mods/noita-mapcap/files/ui.lua")
 
 ---Called in order upon loading a new(?) game.
 function OnModPreInit()
+	-- Override virtual resolution and some other stuff.
+	--ModMagicNumbersFileAdd("mods/noita-mapcap/files/magic-numbers/64.xml")
+	--ModMagicNumbersFileAdd("mods/noita-mapcap/files/magic-numbers/fast-cam.xml")
+	--ModMagicNumbersFileAdd("mods/noita-mapcap/files/magic-numbers/no-ui.xml")
+	--ModMagicNumbersFileAdd("mods/noita-mapcap/files/magic-numbers/offset.xml")
+
+	-- Remove hover animation of newly created perks.
+	ModLuaFileAppend("data/scripts/perks/perk.lua", "mods/noita-mapcap/files/overrides/perks/perk.lua")
 end
 
 ---Called in order upon loading a new(?) game.
@@ -83,6 +92,11 @@ end
 function OnWorldPostUpdate()
 	-- Draw UI after coroutines have been resumed.
 	UI:Draw()
+
+	-- Reload mod every 60 frames.
+	-- This allows live updates to the mod while Noita is running.
+	-- !!! DISABLE THIS LINE AND THE CORRESPONDING REQUIRE BEFORE COMMITTING !!!
+	LiveReload:Reload("mods/noita-mapcap/", 60)
 end
 
 ---Called when the biome config is loaded.
@@ -111,16 +125,3 @@ end
 ---Please be careful with this, as not everything will behave well when called while the game is paused.
 function OnPausePreUpdate()
 end
-
----------------
--- Overrides --
----------------
-
--- Override virtual resolution and some other stuff.
---ModMagicNumbersFileAdd("mods/noita-mapcap/files/magic-numbers/64.xml")
---ModMagicNumbersFileAdd("mods/noita-mapcap/files/magic-numbers/fast-cam.xml")
---ModMagicNumbersFileAdd("mods/noita-mapcap/files/magic-numbers/no-ui.xml")
---ModMagicNumbersFileAdd("mods/noita-mapcap/files/magic-numbers/offset.xml")
-
--- Remove hover animation of newly created perks.
-ModLuaFileAppend("data/scripts/perks/perk.lua", "mods/noita-mapcap/files/overrides/perks/perk.lua")